1. Field of the Invention
The present invention relates generally to a work machining method such as machine cutting and grinding.
2. Description of the Prior Art
In machine cutting or grinding with a machine tool, it is a conventional practice to supply or feed coolant to a position where the machine tool makes contact with a workpiece. A coolant feeder for this purpose is proposed as TOKKAIHEI (Japanese Provisional Publication) No. 8-197311, the coolant feeder being used for a multispindle automatic lathe. In the disclosed coolant feeder, coolant passages 52a, 53a, which are connected, are made in an x-axis slide 52 and a tool rest 53, respectively, of a cross slide 51 for holding a cutting tool 50, as shown in FIG. 21. In addition, one end opening of the coolant passage 52a of the x-axis slide 52 is connected via a distribution passage 54 (which is made of a tube or the like so as to be able to follow the tool rest 53) with a coolant supplier (not shown) while one end opening of the coolant passage 53a of the tool rest 53 is provided with a coolant supply pipe 55. In machining a workpiece 56, a coolant is fed through the distribution passage 54 and the coolant passages 52a, 53a, into the coolant supply pipe 55, and is ejected to a contacting point between the cutting tool 50 and the workpiece 56 from the tip at the open end of the coolant supply pipe 55. Further, this apparatus is designed in such a manner that a coolant is supplied to a tool on a tool slide (not shown). In the figure, 57 is a spindle carrier and 58 is a main axis.
However, in the above coolant feeder, only one kind of coolant is supplied to the contacting point between the cutting tool 50 and the workpiece 56 from one direction, which results in an insufficient cooling effect and insufficient lubricity. For this reason, there are problems of insufficient durability of the cutting tool 50 and poor finishing accuracy of the machined surface on the workpiece 56. Further, there is another problem from an environmental viewpoint in the case of using liquids like cooling water or oil cutting fluid as a coolant, because there is a necessity for the disposal of waste liquids.
Accordingly, it is an object of the present invention to provide a work machining method whereby the durability of a machining tool and the finishing accuracy of a machined surface on a work are superior and no environmental problem is caused.